Resultant force and its representation

Question

An object of 3 kg mass with velocity in x-axis defined by the equation v_x=5-2t. What is the magnitude of the resultant force's representation in the x-axis?

Answer: -6N

Answer 1

Solution:

The expression for velocity Vx = 5-2t find the acceleration ax in the x direction

ax = dv/dt = d(5-2t)/dt = -2 m/s² with ax having same direction as Vx

The Magnitude of the force Fx = m ax with Fx having same direction as ax

F= 3kg ( -2 m/s²) = -6 kg.m/s² = -6N